Coin-actuated crankcase pump control circuit

ABSTRACT

This invention relates to an improved electrical circuit for controlling the operation of a crankcase pump which is characterized by a coin-actuated 110 V. pump motor actuating circuit and an overriding low-voltage pump shut-down circuit that monitors the flow of fluid and responds to the cessation thereof. The circuit also includes a manual starting switch that enables the operator to delay initiation of the pumping cycle so that it will not begin upon insertion of the coin. The pump shutdown circuit has a time-delay feature which prevents premature termination of the pumping cycle initiated by a false response by the fluid-flow sensor. Finally, the circuit provides the operator with a signal that denoted completion of the pumping cycle.

United States Patent [191 Garman COIN-ACTUATED CRANKCASE PUMP CONTROLCIRCUIT [75] Inventor: Mark B. Garman, Grand Junction,

[73] Assignee: Monarch Enterprises, Inc., Grand Junction, C010.

[22] Filed: Dec. 27, 1971 [21] Appl. No.: 212,603

FLOW

RESPONS/VE 11] 3,726,607 451 Apr. 10, 1973 Primary ExaminerCarlton R.Croyle Assistant Examiner-Richard J. Sher Att0meyAnderson, Spangler &Wymore 57] ABSTRACT This invention relates to an improved electricalcircuit for controlling the operation of a crankcase pump which ischaracterized by a coin-actuated 110 V. pump motor actuating circuit andan overriding lowvoltage pump shut-down circuit that monitors the flow Iof fluid and responds to the cessation thereof. The circuit alsoincludes a manual starting switch that enables the operator to delayinitiation of the pumping cycle so that it will not begin upon insertionof the coin. The pump shutdown circuit has a time-delay feature whichprevents premature termination of the pumping cycle initiated by a falseresponse by the fluid-flow sensor.- Finally, the circuit provides theoperator with a signal that denoted completion of the pumping cycle.-

5 Claims, 1 Drawing Figure A CONTROL TIME DELAY COIN-ACTUATED CRANKCASEPUMP CONTROL CIRCUIT in recent years, do-it-yourself coil-operated carwash facilities have become increasingly popular. The

vehicle owner generally finds he can wash his own car in a few minutestime at a cost of a quarter or two.

Generally speaking, the same person who is willing to wash his own carwould not be adverse to changing the oil in it provided there was aconvenient way to drain the crankcase and dispose of the dirty oil. Mostsocalled "discount stores, of which there are many, offer even majorbrands of oil at about half what it costs in the service station and itcertainly does not require any particular skill to open the can and pourit into the crankcase through the fill-pipe.

Draining the oil from the crankcase by removing the drain plug in thepan as is done by the service station attendant presents certainproblems to the vehicle owner because he has no hoist available to him;therefore, about the only practical way left is to suck the dirty oilback up out of the dip stick tube which reaches all the way to thebottom of the crankcase. There is no particular problem encounted indoing so and the pumping equipment is readily available commercially;however, its use demands a certain amount of skill and experience thatone cannot be sure that the average passenger car owner possesses.

Accordingly, provision must be made to protect both the equipment andthe operator against improper use of the equipment while, at the sametime, insuring its satisfactory operation in substantially all types andstyles of automotive vehicles. To accomplish this end, several thingsmust be considered, probably the most important of which is to not runthe pump dry. A variable pumping cycle should be provided that isautomatically adjustable to the requirements of each different vehicle.Most important, the unit must be perfectly safe to use on any type ofvehicle and by even the most inexperienced person.

It has now been found in accordance with the teaching of the presentinvention that a novel coiloperated circuit for controlling theoperation of a crankcase pump possessing the previously-describedattributes can, in fact, be made. It becomes operable for apredetermined time interval sufficient to drain the crankcase of any onevehicle, but not two, upon insertion of a coin of appropriatedenomination. The pumping cycle is initiated at the will of the operatorwhenever he wishes during the preset interval, whereas, the cycle isterminated automatically whenever the crankcase is pumped dry. Uponcompletion of the pumping cycle, the pump is shut down following thelapse of a short time interval selected to insure that the monitorcircuit has not responded to a false signal indicating flow had stopped.

It is, therefore, the principal object of the present in vention toprovide a novel and improved electrical circuit for controlling theoperation of a crankcase pump.

A second objective of the invention forming the subject matter hereof isthe provision of a system of the type aforementioned which automaticallyshuts down the pump when the crankcase is completely drained and no moreoil flows.

Another object of the within-described invention is to provide a unitfor draining automobile crankcases that is programed to operate uponactuation by a single coin over a time interval sufficient to serviceany one vehicle but seldom, if ever, two.

Still another objective is the provision of an electrically-controlledapparatus for draining crankcases that includes means for ignoringspurious signals that would falsely indicate the pumping cycle wascomplete.

An additional object is to provide a crankcase pump control circuit thatallows the user to initiate the pumping cycle but terminates itautomatically. Further objects of the invention herein disclosed andclaimed are to provide a pump control circuit that is safe, versatile,easy to service and repair, simple, fool-proof and reliable.

Other objects will be in part apparent and in part pointed outspecifically hereinafter in connection with the description of thesingle figure of drawings that illustrates in schematic form the controlcircuit of the present invention together with the pumping apparatuscontrolled thereby.

Referring next to the Drawing for a detailed description of theinvention, the letter M has been selected to designate the electricmotor used to drive the pump P which is connected to suck the oil from avehicle crankcase (not shown) through nozzle 10 on the end of vacuumhose 12. The pump delivers the oil to a sump 14 through a drain hose 16.

Nozzle 10 is preferably notched as shown at 18 to prevent itsbottoming-out in the pan and thus restricting the oil flow. The diameterof the nozzle is such as to easily pass down into the crankcase of anautomotive vehicle through its dip stick tube. The length of the tubemust, of course, be sufficient to reach to the bottom of the crankcaseand rest on the pan. Actually, none of the above-described apparatus isnovel nor is the use of the several items in combination with oneanother for the purpose of sucking oil out of a crankcase a new idea.Instead, it is the control circuitry used to oversee the system andprevent its misuse that is unique and, therefore, patentable.

The control circuit forming the subject matter hereof has beendesignated broadly by reference numeral 20 and it will be seen toinclude a 1 10 V. branch identified by reference numeral and alow-voltage 24 V. branch similarly denominated by reference numeral 24.A source 'of 60 cycle 110 V. alternating current 22 supplies current toboth the 110 V. and 24 V. branches of the control circuit 20 through adouble-pole singlethrow coin-controlled master switch 26.

Master switch 26 is normally open and closes upon insertion of a coin ofproper denomination. Once closed, an automatic timer incorporatedtherein is triggered and holds it closed for a predetermined timeinterval. Coin-actuated timer switches such as this are, of course,common shelf items that are widely available in the market place. Inthis particular circuit, an interval of about five minutes more or lesshas proven to be just about right. It is long enough to insure that eventhe largest capacity crankcase will be completely drained even whenfilled with viscous oil, yet, at the same time the interval is too shortto permit two vehicles to be drained on the same coin. This is becausepump P is preferably selected with a capacity such that it requires aminimum of about 2 minutes to drain the minimum capacity crankcase andthe 3 minutes left on the timer is insufficient to drain a secondvehicle. For instance,

even if we assume the first user had the nozzle in place in the dipstick hole and that he initiated the pumping cycle as soon as the coinwas deposited, he would probably use up most, if not all, of theremaining time in removing the nozzle, refilling the crankcase withfresh oil and driving out of the service bay. During whatever time thatremains, the second user would have to drive his car into the servicearea, raise the hood, remove the dip stick from its tube and insert thenozzle before he could even begin the pumping operation. If, as willmost always be the case, there is insufficient time left to completelydrain the second crankcase, another coin will have to be used anyway toinsure that no dirty oil remains in the system to contaminate the freshoil. Thus, while it is certainly possible to temporarily disable thesystem following a single paid-for use, to do so would unnecessarilycomplicate the circuit when it is far simpler, and just as effective tomerely choosethe right time interval during which the operation is to becompleted.

The 110 V. circuit 110 is tapped off the contacts of master switch 26and wired across the contacts 28 of motor M as shown. Current forthe-low-voltage starter subcircuit 248 is taken from circuit 1 throughtransformer T that forms an integral-part of conventional 1 10 V. 24 V.switching relay 30. The 24 V. secondary of transformer T energizes coil32 of relay 34 upon closure of normally-open momentary contact switch36. As relay 34 is energized, it actuates normally-open motor controlswitch 38 in the 110 V. circuit to start the motor M.

Another 24 V. pump monitor circuit 24M is powered by the secondary 40 oftransformer T The primary 42 of this transformer is connected across theterminals of master switch 26 as shown. Circuit 24M includes a vacuumswitch 44 connected into the vacuum side of pump P. This switch is anormallyopen one adapted to sense the flow of oil in hose 12 and respondto such flow by closing. As it does so, a circuit is completed throughsignal 46 which tells the user that the system is pumping oil. Signal46, in the particular form shown, constitutes a lamp but it could be anaudible signal just as well.

Closure of vacuum switch 44 also energizes the coil 48 of time-delayrelay 50 which, in turn, closes normally open switch 52. The latterswitch is connected in parallel with switch 36in starter circuit 248 andit functions to hold relay 30 energized when the user releasesstartswitch 36 to its normally open position. Relay 50 is, once again,of conventional design, and it incorporates a time-delay ofapproximately 30 seconds to a minute during which the pump will continueto operate even though no fluid is flowing and vacuum switch 44 hasreopened. The reason for this is to prevent a premature shutdown of thesystem in the event of a false indication that the crankcase is emptysuch asmight be caused by anair bubble in the line or the like. If, infact, the indication is a false one, the time-delay feature permits'thepump to continue operating long enough to start the fluid flowing again,whereupon, the vacuum switch will reclose returning the system to normalhowever he has no way the crankcase and tha the pumping operation ISincomplete. For all practical purposes, the time-delay feature in the 24V. holding circuit 241-! that includes switch S2 and relay 30 overcomesthis problem;

What is claimed is:

1. The control circuit for operating an electricallydriven suction pumpof the type used to pump oil out of the crankcase of an automotivevehicle which comprises: an electric pump motor connectable to a sourceof electrical energy to define a main motor circuit; a firstnormally-open relay-actuated switch connected in the main motor circuitin series with the motor; a second normally-open relay-actuated switchconnected in series with the relay of the first relay-actuated switchand connectable to a source of electrical energy to define a holdingcircuit; a normally-open fluid-actuated switch responsive to the flow offluid through the pump connected in series with the relay of the secondrelayactuated switch means and connectable to a source of electricalenergy to define a sensing circuit; and, a normally-openmanually-actuatedswitch connected in se ries with the relay of the firstrelay-actuated switch means and in parallel with the secondrelay-actuated switch means to define a starting circuit, said startingcircuit being operative upon closure of the manuallyactuated switchmeans to actuate the main motor circuit and start the motor, the sensingcircuit being operative upon actuation of the main motor circuit in amanner to cause fluid flow so as to actuate the holding circuit and keepthe main motor circuit actuated upon deactivation of the startingcircuit, and said sensing circuit beingresponsive to discontinuance ofthe fluid flow through the pump to deactivate the holding circuitthereby deactivating the main motor circuit if the starting circuit isdeactivated.

2. The suction pump control circuit as set forth in claim 1 whichincludes: signaling means connected in the sensing circuit in serieswith the fluid-actuated switch means and in parallel with the relay ofthe second relay-actuated switch means, said signaling means beingoperative to indicate the flow of fluid through the pump so long as saidsensing circuit is activated.

3. The suction pump control circuit as set forth in claim 1 whichincludes: normally-open coin-actuated switch means connected into themain-motor circuit in series with the first relay-actuated switch means,said switch means being operative in closed position with said firstrelay-actuated switch means closed to activate said main motor circuitfor a predetermined time interval.

' 4. The suction pump control circuit as set forth in claim 1 in which:the second relay-actuated switch means is of a time-delay type operativeupon actuation to remain actuated for a predetermined time intervalfollowing deactivation of the sensing circuit.

5 The suction pump control circuit as set forth in claim 3 in which: thecoin-actuated switch is timed to remain closed for an interval ofapproximately 5 minutes.

1. The control circuit for operating an electrically-driven suction pumpof the type used to pump oil out of the crankcase of an automotivevehicle which comprises: an electric pump motor connectable to a soUrceof electrical energy to define a main motor circuit; a firstnormally-open relay-actuated switch connected in the main motor circuitin series with the motor; a second normally-open relay-actuated switchconnected in series with the relay of the first relay-actuated switchand connectable to a source of electrical energy to define a holdingcircuit; a normally-open fluid-actuated switch responsive to the flow offluid through the pump connected in series with the relay of the secondrelay-actuated switch means and connectable to a source of electricalenergy to define a sensing circuit; and, a normallyopenmanually-actuated switch connected in series with the relay of the firstrelay-actuated switch means and in parallel with the secondrelay-actuated switch means to define a starting circuit, said startingcircuit being operative upon closure of the manually-actuated switchmeans to actuate the main motor circuit and start the motor, the sensingcircuit being operative upon actuation of the main motor circuit in amanner to cause fluid flow so as to actuate the holding circuit and keepthe main motor circuit actuated upon deactivation of the startingcircuit, and said sensing circuit being responsive to discontinuance ofthe fluid flow through the pump to deactivate the holding circuitthereby deactivating the main motor circuit if the starting circuit isdeactivated.
 2. The suction pump control circuit as set forth in claim 1which includes: signaling means connected in the sensing circuit inseries with the fluid-actuated switch means and in parallel with therelay of the second relay-actuated switch means, said signaling meansbeing operative to indicate the flow of fluid through the pump so longas said sensing circuit is activated.
 3. The suction pump controlcircuit as set forth in claim 1 which includes: normally-opencoin-actuated switch means connected into the main motor circuit inseries with the first relay-actuated switch means, said switch meansbeing operative in closed position with said first relay-actuated switchmeans closed to activate said main motor circuit for a predeterminedtime interval.
 4. The suction pump control circuit as set forth in claim1 in which: the second relay-actuated switch means is of a time-delaytype operative upon actuation to remain actuated for a predeterminedtime interval following deactivation of the sensing circuit. 5 Thesuction pump control circuit as set forth in claim 3 in which: thecoin-actuated switch is timed to remain closed for an interval ofapproximately 5 minutes.